1. Field of the Invention
The present invention relates to a power system control apparatus and a power system control method in which voltage and reactive power in a power system are adjusted to desired values by operating a control apparatus of the power system.
2. Description of Related Art
As is disclosed in pages 1200-1201 of lectures of a National Conference of Japanese Electrotechnical Committee held in 1987, in a conventional power system control method, a voltage of a first substation corresponding to one power system and a reactive power flow transmitted through a bank are measured, and phase modifying equipment (for example, a transformer tap, a condenser, a reactor and the like) arranged in the first substation is controlled according to measured values.
Accordingly, in cases where the first substation is isolated from another substation, a voltage fluctuation in the first substation can be suppressed according to the conventional power system control method by controlling the phase modifying equipment.
However, in cases where the first substation is connected with a second substation, because a voltage fluctuation of the second substation adjacent to the first substation is not considered, there is a drawback that voltages of the first and second substations adjacent to each other become unstable.
Also, to prevent hunting in a control operation repeatedly performed in the phase modifying equipment by suppressing voltage fluctuations occurring in substations (or power systems) adjacent to each other, a method for controlling all apparatus of the power systems adjacent to each other by collecting all information of the power systems as one package is disclosed in pages 1115-1120, Vol. B117-8, theses in Japanese Electrotechnical Committee. However, in this method, the amount of data included in the information is too large to be processed, so it is difficult to increase control precision of the apparatus because it is required to identify the power systems, and a control time period for the apparatus is undesirably lengthened.